In an LCD panel of advanced super dimension switch (ADS) type, an electric field generated at edges of slit electrodes arranged in the same plane and an electric field generated between a slit electrode layer and a plate electrode layer form a multidimensional electric field such that liquid crystal molecules in all orientations between the slit electrodes and right over the electrodes in a liquid crystal cell can be rotated to improve efficiency of liquid crystal and increase light transmittance.
However, when an ADS type LCD panel is compressed forcefully, an opposing substrate disposed above an array substrate is displaced. If a black matrix over a gate line is not wide enough, light leakage easily occurs from a side of the gate line, resulting a poor quality of images in the LCD panel. In prior art systems, typically a shielding electrode is used to shield an electric field above a gate line, such that even if the LCD panel including the array substrate is displaced under effect of an external force, the deflection of the liquid crystal molecules will not be affected and thus light leakage around the gate lines can be eliminated.
On the other hand, in order to avoid light leakage at a data line, typically a black matrix disposed over the data line and covering the data line is made to have a larger width. As a result, although the width of the black matrix over a gate line is reduced by using a shielding electrode, the actual effect of increasing aperture ratio of the LCD panel is limited, and the actual effect of increasing utilization efficiency of liquid crystal is also limited.
For the above reasons, there is still a need to further improve aperture ratio and transmittance of an LCD panel while satisfying gate line shielding.